From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>
Subject: Re: I2C from interrupt context?
Date: Thu, 06 Nov 2008 15:47:54 -0800 (PST)
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From: Krzysztof Halasa <khc-9GfyWEdoJtJmR6Xm/wNWPw@public.gmane.org>
Date: Fri, 07 Nov 2008 00:44:48 +0100

[ Fixed i2c list address, it's now hosted at vger ]

> I'm updating my EEPROM console logger and have encountered a problem
> - the logger (as any console) can be called with hardware interrupts
> disabled and/or from interrupt context. It needs to write to I^2C
> (using ARM (Xscale) GPIO) and possibly SMBUS-only EEPROM chip. Is it
> at all supposed to be possible?

Not really.  The I2C operations need to be able to sleep and that's
not allowed in interrupt context.